TWI762639B - Controlled residence cmp polishing method - Google Patents

Abstract

The invention provides a method for polishing or planarizing a wafer of at least one of semiconductor, optical and magnetic substrates. The method includes rotating a polishing pad, the rotating polishing pad having radial feeder grooves in the polishing layer separating the polishing layer into polishing regions. The polishing regions are circular sectors defined by two adjacent radial feeder grooves. The radial feeder grooves extend from a location adjacent the center to a location adjacent the outer edge. Each polishing region includes a series of biased grooves connecting a pair of adjacent radial feeder grooves. Pressing and rotating the wafer against the rotating polishing pad for multiple rotations of the polishing pad adjusts polishing by either increasing or decreasing residence time of the polishing fluid under the wafer.

Description

CMP polishing method with controllable residence time

The present invention relates to grooves for chemical mechanical polishing pads. More particularly, the present invention relates to trench designs for increasing removal rates, increasing overall uniformity, and reducing defects during chemical mechanical polishing.

In the manufacture of integrated circuits and other electronic devices, multiple layers of conductor, semiconductor, and dielectric materials can be deposited and removed from surfaces on semiconductor wafers. Thin layers of conductor, semiconductor, and dielectric materials can be deposited using a variety of deposition techniques. Common deposition techniques in modern wafer processing include Physical Vapor Deposition (PVD), also known as Sputtering; Chemical Vapor Deposition (CVD); Plasma Enhanced Chemical Vapor Deposition (PECVD) and Electrochemical Plating. Common removal techniques include wet and dry isotropic and anisotropic etching, among others.

As layers of material are sequentially deposited and removed, the uppermost surface of the wafer becomes uneven. Wafers need to be planarized because subsequent semiconductor processing, such as metallization, requires the wafer to have a flat surface. Planarization is useful for removing undesired surface topography and surface defects, such as rough surfaces, coalesced material, lattice damage, scratches, and contaminated layers or materials.

Chemical mechanical planarization or chemical mechanical polishing (CMP) is a common technique used to planarize or polish workpieces such as semiconductor wafers. In conventional CMP, a wafer carrier or polishing head is mounted on a carrier assembly. The polishing head holds and positions the wafer in contact with the polishing layer of a polishing pad mounted on a platen or platen inside the CMP apparatus. The carrier assembly provides controlled pressure between the wafer and polishing pad. At the same time, a polishing medium, such as a slurry, is dispensed onto the polishing pad and drawn into the gap between the wafer and polishing layer. The polishing pad and wafer are typically rotated relative to each other to polish the substrate. As the polishing pad rotates under the wafer, the wafer sweeps out a typical annular polishing track or polishing area, where the wafer surface is directly facing the polishing layer. The wafer surface is polished and planarized by chemical and mechanical action of the polishing layer and polishing medium on the surface.

Reinhardt et al., US Patent No. 5,578,362 discloses the use of grooves to provide macrotexture to the pad. In particular, it discloses various patterns, contours, grooves, spirals, radials, dots or other shapes. Specific examples included in Reinhardt are concentric circles and concentric circles overlapping X-Y trenches. Concentric circular grooves have proven to be the most popular groove pattern since they do not provide a direct flow path to the edge of the pad.

Lin et al., US Patent No. 6,120,366 Fig. 2 discloses a combination of circular and radial feed troughs. This example illustrates the addition of 24 radial feed troughs to a concentric circular groove pattern. The disadvantage of this groove pattern is that it provides limited polishing improvement due to the smaller landing area on the polishing pad, greatly increases slurry usage and reduces pad life.

Nonetheless, there continues to be a need for chemical mechanical polishing pads with better combinations of polishing performance and slurry dosage. In addition, there is a need for trenches that increase removal rates, reduce slurry usage, improve overall uniformity, and reduce defects during chemical mechanical polishing.

One aspect of the present invention provides a method for polishing or planarizing a wafer of at least one of semiconductor, optical and magnetic substrates, the method comprising the following: a spinning polishing pad having: having a polymer A polishing layer of a substrate and thickness, the polishing layer including a center, an outer edge, and a radius extending from the center to the outer edge of the polishing pad; a radial feed slot in the polishing layer, the diameter Separating the polishing layer into a polishing area toward a feed slot, the polishing zone being a circular sector bounded by two adjacent radial feed slots from a location adjacent to the center extending at least to a location adjacent to said outer edge; and each polishing zone, each polishing zone comprising a series of offset grooves connecting a pair of adjacent radial feed troughs, a majority of offset grooves being offset inwardly towards said The center of the polishing pad or outwardly biased toward the outer edge of the polishing pad, the inwardly biased grooves and the outwardly biased grooves move the polishing fluid toward the outer edge of the polishing pad and toward the wafer or away from the wafer depending on the inward or outward bias and the direction of rotation of the polishing pad; the slurry is dispensed onto the rotating polishing pad and into the radial feed slot and a series of offsets and, in the case of multiple rotations of the polishing pad, rotating the wafer against the rotating polishing pad to adjust polishing by the following options: i) During the counterclockwise rotation of the polishing pad, if a A series of offset grooves are offset inwards towards the center of the rotating polishing pad, prolonging the residence time of the polishing solution under the wafer, or shortening if a series of offset grooves are offsetting outwardly towards the outer edge of the rotating polishing pad. The residence time of the polishing solution under the wafer; or ii) during the clockwise rotation of the polishing pad, if a series of offset grooves are deflected inwardly towards the center of the rotating polishing pad, the residence time of the polishing solution under the wafer is shortened , or if a series of offset grooves are deflected outward toward the outer edge of the rotating polishing pad, the residence time of the polishing solution under the wafer is prolonged.

Another aspect of the present invention provides a method for polishing or planarizing a wafer of at least one of semiconductor, optical and magnetic substrates, the method comprising the following: a spinning polishing pad having: having A polishing layer of a polymer matrix and thickness, the polishing layer including a center, an outer edge, and a radius extending from the center of the polishing pad to the outer edge; a radial feed slot in the polishing layer, the radial feed slot The polishing layer is divided into polishing regions, which are circular sectors bounded by two adjacent radial feed troughs, a bisector that bisects the polishing region, the radial feed troughs extending from adjacent to The location of the center extends at least to a location adjacent to the outer edge; and each polishing area includes a series of offset grooves connecting a pair of adjacent radial feed grooves, a majority of the offset grooves The grooves are deflected inwardly toward the center of the polishing pad at an angle of 20° to 85° from the bisector or outwardly toward the outer edge of the polishing pad at an angle of 95° to 160° from the bisector. an outer bias groove moves the polishing fluid toward the outer edge of the polishing pad and toward the wafer or away from the wafer depending on the inward or outward bias and the direction of rotation of the polishing pad; Dispensing the polishing liquid onto the rotating polishing pad and into a radial feed slot and a series of offset grooves; and rotating the wafer against the rotating polishing pad with multiple rotations of the polishing pad, To adjust polishing by the following options: i) prolong the residence time of the polishing solution under the wafer if a series of offset grooves are inwardly biased towards the center of the rotating polishing pad during counterclockwise rotation of the polishing pad, or If the series of offset grooves are deflected outwardly towards the outer edge of the rotating polishing pad, the residence time of the polishing solution under the wafer is shortened; or ii) during clockwise rotation of the polishing pad, if the series of offset grooves If a series of offset grooves are deflected outward to the outer edge of the rotating polishing pad, the residence time of the polishing liquid under the wafer will be shortened, or if the series of offset grooves are outwardly biased to the outer edge of the rotating polishing pad, the polishing liquid will be prolonged under the wafer. residence time.

The groove patterns and methods of the present invention provide for controlled and uniform distribution of polishing slurries, such as abrasive-containing slurries and abrasive-free polishing solutions. The efficient distribution allows the user to reduce slurry flow compared to conventional grooves. Additionally, the interconnected trench paths allow polishing debris to exit the pad in an efficient manner to reduce polishing defects. Finally, the groove pattern improves polishing uniformity, wafer profile, die size uniformity and can improve edge effects.

The term " trapezoid " as used herein and within the scope of the claims refers to interconnect trenches that form a quadrangle or quadrilateral having only one pair of parallel sides. A trapezoid has two parallel bases and two sides connecting the bases. All angles of the trapezoid add up to 360°.

The term " non-isosceles trapezoid " as used herein and within the scope of the claims refers to interconnect trenches that form a trapezoid with two unequal sides or sides of different lengths. Edges closer to the center of the pad are shorter in length than edges closer to the perimeter.

The term " circular sector " as used herein and in the scope of the claims refers to a portion of a polishing pad bounded by two radial feed troughs and a peripheral arc extending along the outer edge of the polishing pad. The radial feed troughs may have straight radials, curved radials, stepped radials, or other shapes.

The term " polishing fluid " as used herein and within the scope of the claims refers to an abrasive-containing polishing slurry or an abrasive-free polishing solution.

The term " offset angle Θ " as used herein refers to the angle between the bisector that bisects the polishing area and the obliquely offset groove connecting adjacent radial feed troughs. The bisector moves as the direction of the radial feeder slot changes and represents the end-to-end average of each offset slot.

The term " inward deflection angle θ " as used herein and in the scope of the claims refers to the deflection angle that is tilted inward toward the center of the polishing pad, as measured from left to right when viewed downward toward the top of the trench.

The term " outward deflection angle θ " as used herein and in the scope of the claims refers to the deflection angle of the perimeter slope of the outwardly facing polishing pad, as measured from left to right when viewed downward toward the top of the groove.

The term " wafer " includes magnetic, optical and semiconductor substrates. Conventions contained in this specification, such as wafer residence time, assume that the polishing droplet drop point is on the left side of the wafer with counterclockwise rotation and on the right side of the wafer with clockwise rotation, as in the top view seen.

The term " poly ( urethane) " as used herein and in the scope of the appended claims is a polymer formed by the reaction between an isocyanate and a compound containing an active hydrogen group, specifically including the following: (a) (i) polyurethanes formed by the reaction of isocyanates and (ii) polyols (including diols); and (b) from (i) isocyanates and (ii) polyols (including diols) and (iii) water A poly(urethane) formed by the reaction of , amine, or a combination of water and amine. The polishing pads of the present invention are advantageously polymers, but most advantageously polyurethane polymers.

The trench patterns of the present invention provide various benefits. The first benefit is that most of the offset trenches sweep across the wafer in the same direction. All offset trenches are swept in the same direction to further increase the benefit. Sweeping the wafer in the same direction causes the trenches to sweep across the wafer rhythmically and provides a beneficial cumulative effect on the polishing removal rate. Furthermore, because the offset grooves are aligned in the same direction, polishing the wafer can be done without oscillating the carrier head or oscillating it with a much smaller amplitude or slower oscillation rate. This allows the wafer to be polished in a fixed position farther from the center of the pad and closer to the edge of the polishing pad. The liner rotates faster at these locations near the outer edge than the center, further increasing the removal rate. In addition, with polishing pads and retaining rings, polishing in a non-oscillating mode can provide a consistent edge profile to multiple wafers and reduce defects, improving pad life and retaining ring life due to reduced wear. Turning off oscillation also allows the use of manufacturing tools with reduced platen size. This is especially important for dual platen and 450 mm size CMP tools. Additionally, the number of radial slots, platen speed and deflection angle Θ can be used in combination to adjust the center profile between fast and slow speeds and provide a consistent flat profile.

In addition, the combination of the feed slot and the offset slot can promote uniform distribution of the slurry across the polishing pad and provide better distribution of the slurry across the wafer surface. This allows adjustment of the polishing rate distribution across the wafer, improving overall uniformity by changing platen speed or deflection angle Θ or both. In addition, the wafer edge profile can also be adjusted by optimizing the deflection angle θ or the carrier speed or both. In advanced logic and 3D NAND, this is even more important for edge exclusion with very low wafer edge yields. Typically, polishing pads have at least three feed troughs, and can range from 3 to 32 grooves. Typically, wafers alternate between one radial feed slot and offset slots and across two or more radial feed slots and offset slots. This uniform distribution eliminates build-up at the carrier ring and allows the polishing pad to operate in a more efficient manner or with reduced slurry flow.

Another unexpected feature of the present invention is that it allows polishing at higher downforce than conventional trenches due to better slurry distribution on the wafer surface and reduced wafer-pad overheating and polishing temperature. This is especially important for CMP metal polishing such as copper, tantalum and tungsten polishing. These metal layers, dielectric layers, insulating layers and other material layers all represent wafer components. The groove patterns of the present invention operate in conjunction with porous and non-porous polishing pads. The groove pattern of the present invention is particularly suitable for precision polishing of non-porous polishing pads, such as atomic-level polishing for removing a single single atomic layer at a time.

Because the inwardly and outwardly biased grooves guide the polishing fluid away from the polishing pad, its debris polishing removal is efficient and has fewer defects.

1 and 1A, the polishing pad 10 of the present invention is suitable for polishing or planarizing at least one of semiconductor, optical and magnetic substrates. The polishing layer 12 has a polymer matrix and a thickness 14 . The polishing layer 12 includes a center 16 , an outer edge 18 , and a radius (r) extending from the center 16 to the outer edge 18 . Advantageously, the position of the wafer is positioned along the radius r, from the center 16 of the polishing pad 10 to the outer edge 18 of the polishing pad and then to the center 16 of the polishing pad 10 to increase the removal rate of at least one component of the wafer . The radial feed troughs 20 , 22 , 24 , 26 , 28 , 30 , 32 and 34 start from the center 16 or from the optional circular groove 36 . The radial feed troughs 20 , 22 , 24 , 26 , 28 , 30 , 32 and 34 divide the polishing layer 12 into polishing regions 40 , 42 , 44 , 46 , 48 , 50 , 52 and 54 . In particular, two adjacent radial feed troughs, such as 20 and 22 , in combination with the peripheral arc 19 of the outer edge 18 define a polishing area 40 . Polished area 40 together with polished areas 42 , 44 , 46 , 48 , 50 , 52 and 54 form a circular sector shape with a small circular sector truncated at center 16 . The radial feed troughs 20 , 22 , 24 , 26 , 28 , 30 , 32 and 34 advantageously extend from a circular groove 36 adjacent the center 16 at least to or adjacent the outer edge 18 .

Referring to FIGS. 1A and 1B , polishing area 40 includes a series of stacked trapezoidal trench areas 60 , 62 , 64 , 66 and 68 . Polishing area 40 represents a circular sector of polishing pad 10 (FIG. 1), the central area of which is free of grooves. Parallel linear trenches or parallel base trenches 160 , 162 , 164 , 166 , 168 and 170 define the tops and bottoms of trapezoidal trench regions 60 , 62 , 64 , 66 and 68 . The radial feed trough sections 20a, 20b, 20c, 20d, and 20e of radial feed trough 20 define the left side of trapezoidal groove regions 60, 62, 64, 66, and 68, respectively. The radial feed trough sections 22a, 22b, 22c, 22d and 22e of the radial feed trough 22 define the right side of the trapezoidal groove regions 60, 62, 64, 66 and 68, respectively. Polished regions 40, 42, 44, 46, 48, 50, 52, and 54 (FIG. 1) each include a series of trapezoidal trench regions spaced from parallel substrate trenches. To accommodate the shape of circular polishing pad 10 or the circular sector shape of polishing areas 40 , 42 , 44 , 46 , 48 , 50 , 52 and 54 , trapezoidal groove areas are typically cut to accommodate outer edge 18 or circular groove 36 .

The trapezoidal groove regions 60, 62, 64, 66 and 68 all represent non-isosceles trapezoidal regions in which the radial side segments have different lengths. Since this groove pattern has an inward offset towards the center, radial feed trough sections 20a, 20b, 20c, 20d, and 20e are longer than radials 22a, 22b, 22c, 22d, and 22e, respectively. In addition to each trapezoidal groove region representing a non-isosceles trapezoid, the perimeters of the stacked trapezoid regions, such as the perimeters of trapezoidal regions 60 and 62 and the perimeters of trapezoidal regions 60, 62, and 64, also define the non-isosceles trapezoid. A portion of the trapezoidal region 70 adjacent the circular groove 36 is truncated to accommodate the circular groove 36 . Similarly, portions of trapezoidal groove regions 80 , 82 , 84 , 86 , 88 , 90 , 92 , 94 , 96 and 98 adjacent to outer edge 18 are truncated to accommodate the rounded shape of outer edge 18 of polishing pad 10 . Rotating the polishing pad causes the applied polishing liquid to be sent out of the polishing pad 10 through a portion of a series of offset grooves adjacent to the trapezoidal groove regions 80, 82, 84, 86, 88, 90, 92, 94, 96 and 98 edge 18, thereby allowing fresh slurry to flow under the wafer.

Referring to FIG. 1A , the dashed line AA bisects the polishing area 40 by connecting the center 16 to the midpoint of the peripheral arc 19 of the outer edge 18 . The bases of the spaced trapezoidal trench regions 80, 82, 84, 86, 88, 90, 92, 94 and 96 intersect the line AA at an angle Θ. For the purposes of this description, angle Θ is the upper right corner when the center is at the top and the outer edge is at the bottom, as shown in Figures 1A and 2A. For inwardly offset grooves, the angle θ is preferably 20 to 85°. For inwardly offset grooves, the angle θ is more preferably 30 to 80°. The radial feed trough 20 intersects the trapezoidal groove regions 60 , 62 , 64 , 66 and 68 at an angle α ₁ . The radial feed trough 22 intersects the trapezoidal groove regions 60, 62, 64, 66 and 68 at _an angle β1. For the inwardly offset trapezoidal groove regions 60, 62, 64, 66, and 68, the α1 angle is smaller _than the _β1 angle.

Referring to Figure IB, polishing regions 60, 62, 64, 66, and 68 are a series of spaced-apart non-isosceles trapezoidal trench structures. The trapezoidal groove structure has parallel base sections 160, 162, 164, 166, 168 and 170 which connect two adjacent radial feed troughs 20 and 22 to form side sections 20a, 20b, 20c, 20d and 20e and 22a, 22b, 22c, 22d and 22e. Base segments 160, 162, 164, 166, 168, and 170 intersect each of side segments (20a, 20b, 20c, 20d, and 20e) and (22a, 22b, 22c, 22d, and 22e) at different angles. A series of non-isosceles trapezoidal groove structures extend from adjacent the outer edge toward the center of the polishing pad. The perimeters of the series of trapezoidal structures 60, 62, 64, 66 and 68 are also trapezoidal.

The polishing pad is rotated to move the polishing liquid through the base sections 160, 162, 164, 166, 168 and 170 and the side sections (20a, 20b, 20c, 20d and 20e) and (22a, 22b, 22c, 22d and 22e) towards the polishing pad the outer edge. In addition to moving outward, the slurry moves toward the wafer with clockwise rotation of the polishing pad and away from the wafer with counter-clockwise rotation of the polishing pad. The movement of the slurry towards the wafer reduces the residence time of the slurry under the wafer and away from the wafer extends the residence time of the slurry under the wafer. For example, the inward bias can extend the residence time with counterclockwise rotation of the platen. All polished areas should have the same offset.

Referring to Figure 1C, during rotation, slurry is distributed onto the rotating polishing pad and into radial feed channels 22 (22a, 22b, and 22c) and a series of offset grooves 160, 161, 162, and 163. Centrifugal force moves the slurry through radial feed channels 22 (22a, 22b, and 22c) and a series of offset grooves 160, 161, 162, and 163 toward the outer edge of the polishing pad in the direction of the arrows. In addition, the polishing liquid overflows outward by overflowing the outer walls 160a, 161a, 162a and 163a to wet the landing areas 60a, 61a, 62a and 63a, respectively. Then, the polishing liquid flows into the inner walls 161b and 160b of the subsequent offset grooves 160 and 162, respectively (the other offset grooves are not visible, and the inner walls are not visible for flow along the drop regions 60a and 61a). The flow arrows at the inner wall 160b and the outer wall 160a illustrate the flow of polishing fluid into and out of the inwardly biased groove 160 . Typically, offset trenches 160 and 162 are not aligned with offset trenches 161 and 163 . This misalignment of offset grooves between adjacent polishing areas promotes flow along radial feed channels 22 to improve slurry distribution. In alternative embodiments, the offset grooves of adjacent polishing regions may be aligned. The wafer is rotated against the rotating polishing pad for multiple rotations to remove at least one component of the wafer, wherein the landing areas 60a, 61a, 62a and 63a are all wetted by the overflowing polishing liquid.

1-1C, polishing pad 10 preferably includes at least 20 inwardly offset grooves, such as 160, 162, 164, 166, 168 and 170. These inwardly biased grooves represent groove segments that connect between adjacent radial feed troughs and their combination can extend the residence time of the slurry under the wafer substrate with counterclockwise rotation of the platen. More preferably, polishing pad 10 includes 20 to 1,000 inwardly offset grooves in each polishing area 40 , 42 , 44 , 46 , 48 , 50 , 52 and 54 . Optimally, polishing pad 10 includes 20 to 500 inwardly offset grooves in each polishing area 40 , 42 , 44 , 46 , 48 , 50 , 52 and 54 .

Typically, the total number of inwardly offset grooves (such as 160, 162, 164, 166, 168, and 170) of polishing pad 10 is radial feed grooves 20, 22, 24, 26, 28, 30, 32, and 34 ( 8) At least 15 times the total. For example, the total number of inwardly biased grooves on polishing pad 10 may be 20 to 1,000 times the total number of radial feed troughs 20, 22, 24, 26, 28, 30, 32, and 34(8). Preferably, the total number of inwardly biased grooves on polishing pad 10 may be 20 to 500 times the total number of radial feed troughs 20, 22, 24, 26, 28, 30, 32, and 34(8).

2 and 2A, the polishing pad 210 of the present invention is suitable for polishing or planarizing at least one of semiconductor, optical and magnetic substrates. The polishing layer 212 has a polymer matrix and a thickness 214 . The polishing layer 212 includes a center 216 , an outer edge 218 , and a radius (r) extending from the center 216 to the outer edge 218 . Advantageously, the position of the wafer is positioned along the radius r, from the center 216 of the polishing pad 210 to the outer edge 218 of the polishing pad, and then to the center 216 of the polishing pad 210 to increase the removal rate of at least one component of the wafer . Radial feed troughs 220 , 222 , 224 , 226 , 228 , 230 , 232 and 234 start from center 216 or from optional circular groove 236 . Radial feed channels 220 , 222 , 224 , 226 , 228 , 230 , 232 and 234 separate polishing layer 212 into polishing regions 240 , 242 , 244 , 246 , 248 , 250 , 252 and 254 . In particular, two adjacent radial feed troughs (such as 220 and 222 ) define a polishing area 240 in combination with the peripheral arc 219 of the outer edge 218 . The polishing area 240, along with the polishing areas 242, 244, 246, 248, 250, 252, and 254, has a circular sector shape with a small circular sector truncated at the center 216. The radial feed troughs 220 , 222 , 224 , 226 , 228 , 230 , 232 and 234 advantageously extend from a circular groove 236 adjacent the center 216 at least to or adjacent to the outer edge 18 .

2A and 2B, polishing region 240 includes a series of stacked trapezoidal trench regions 260, 262, 264, 266, and 268. Polishing area 240 represents a circular sector of polishing pad 210 (FIG. 2), the central area of which is free of grooves. Parallel linear trenches or parallel base trenches 360 , 362 , 364 , 366 , 368 and 370 define the tops and bottoms of trapezoidal trench regions 260 , 262 , 264 , 266 and 268 . Radial feed slot sections 220a, 220b, 220c, 220d, and 220e of radial feed slot 220 define the left side of trapezoidal slot regions 260, 262, 264, 266, and 268, respectively. Radial feed slot sections 222a, 222b, 222c, 222d, and 222e of radial feed slot 222 define the right side of trapezoidal slot regions 260, 262, 264, 266, and 268, respectively. Polished regions 240, 242, 244, 246, 248, 250, 252, and 254 (FIG. 2) each include a series of trapezoidal trench regions spaced from parallel substrate trenches. To accommodate the shape of circular polishing pad 210 or the circular sector shape of polishing regions 240 , 242 , 244 , 246 , 248 , 250 , 252 and 254 , trapezoidal groove regions are typically cut to accommodate outer edge 218 or circular groove 236 .

Trapezoidal groove regions 260, 262, 264, 266, and 268 all represent non-isosceles trapezoidal regions in which the radial side segments have different lengths. Since this groove pattern has an outward offset of the outer edge 218, the radial feed slot segments 220a, 220b, 220c, 220d, and 220e are longer than the radials 222a, 222b, 222c, 222d, and 222e, respectively. In addition to each trapezoidal groove region representing a non-isosceles trapezoid, the perimeters of stacked trapezoidal regions, such as the perimeters of trapezoidal regions 260 and 262; and the perimeters of trapezoidal regions 260, 262, and 264, also define the non-isosceles trapezoid . A portion of the trapezoidal region 270 adjacent to the circular groove 236 is truncated to accommodate the circular groove 236 . Similarly, portions of trapezoidal groove regions 280 , 282 , 284 , 286 , 288 , 290 , 292 , 294 and 296 adjacent to outer edge 218 are truncated to accommodate the rounded shape of outer edge 218 of polishing pad 210 . Rotating the polishing pad directs the applied polishing liquid to the outer edge 218 of the polishing pad 210 through a portion of a series of offset grooves adjacent to the trapezoidal groove regions 280, 282, 284, 286, 288, 290, 292, 294 and 296, to allow the new polishing fluid to flow under the wafer.

Referring to FIG. 2A , dashed line AA bisects polishing area 240 by connecting center 216 with the midpoint of peripheral arc 219 of outer edge 218 . The base edges of the spaced trapezoidal trench regions 280, 282, 284, 286, 288, 290 and 292 intersect the line AA at an angle Θ. For the purpose of description, angle Θ is the upper right corner when the center is at the top and the outer edge is at the bottom, as shown in Figures 1A and 2A. For the outwardly offset grooves, the angle θ is preferably 95 to 160°. For the outwardly offset grooves, the angle θ is more preferably 100 to 150°. The radial feed trough 220 intersects the trapezoidal groove regions 260, 262, 264, 266 and 268 at an angle _α2 . The radial feed slot 222 intersects the trapezoidal groove regions 260, 262, 264, 266 and 268 at an angle _β2 . For the outwardly biased trapezoidal trench regions 260, 262, 264, 266 and 268, the _α2 angle is greater than the _β2 angle.

Referring to Figure 2B, polishing regions 260, 262, 264, 266, and 268 are a series of spaced-apart non-isosceles trapezoidal trench structures. The trapezoidal groove structure has parallel base sections 360, 362, 364, 366, 368 and 370 connecting two adjacent radial feed troughs 220 and 222 to form side sections 220a, 220b, 220c, 220d and 220e and 222a, respectively , 222b, 222c, 222d, and 222e. Base segments 360, 362, 364, 366, 368, and 370 intersect each of side segments (220a, 220b, 220c, 220d, and 220e) and (222a, 222b, 222c, 222d, and 222e) at different angles. A series of non-isosceles trapezoidal groove structures extend from adjacent the outer edge toward the center of the polishing pad. The perimeters of a series of trapezoidal structures 260, 262, 264, 266 and 268 are also trapezoidal.

The polishing pad is rotated to move the polishing liquid through the base sections 360, 362, 364, 366, 368 and 370 and the side sections (220a, 220b, 220c, 220d and 220e) and (222a, 222b, 222c, 222d and 222e) towards the polishing pad the outer edge. In addition to moving outward, the slurry moves toward the wafer with clockwise rotation of the polishing pad and away from the wafer with counter-clockwise rotation of the polishing pad. Movement of the slurry toward the wafer reduces the residence time of the slurry under the wafer, and movement away from the wafer extends the residence time of the slurry under the wafer. For example, the outward bias can reduce residence time with counter-clockwise rotation of the platen. All polished areas should have the same offset.

Referring to Figure 2C, during rotation, slurry is distributed onto the rotating polishing pad and into radial feed channels 222 (222a, 222b, and 222c) and a series of offset grooves 360, 361, 362, and 163. Centrifugal force moves the slurry through radial feed channels 222 (222a, 222b, and 222c) and a series of offset grooves 360, 361, 362, and 363 toward the outer edge of the polishing pad in the direction of the arrows. In addition, the polishing liquid moves outward by overflowing the outer walls 360a, 361a, 362a and 363a, thereby moistening the landing areas 260a, 261a, 262a and 263a, respectively. The slurry then flows into the inner walls 361b and 360b of subsequent offset grooves 360 and 362, respectively (the other offset grooves are not visible and the inner walls are not visible for flow along landing areas 60a and 61a). The flow arrows at the inner wall 360b and the outer wall 360a illustrate the flow of slurry into and out of the outwardly biased groove 360 . Typically, offset trenches 360 and 362 are not aligned with offset trenches 361 and 363 . This misalignment of the offset grooves between adjacent polishing areas promotes downward flow along the radial feed slot 222 to improve slurry distribution. In alternative embodiments, the offset grooves of adjacent polishing regions may be aligned. The wafer is rotated against the rotating polishing pad for multiple rotations to remove at least one component of the wafer, wherein the landing areas 260a, 261a, 262a and 263a are all wetted by the overflowing polishing liquid.

2-2C, polishing pad 210 preferably includes at least 20 outwardly offset grooves, such as 260, 262, 264, in each polishing area 240, 242, 244, 246, 248, 250, 252, and 254 , 266, 268 and 270. These outwardly offset grooves represent groove segments connected between adjacent radial feed grooves; and their combination reduces the residence time of the slurry under the wafer substrate with counterclockwise rotation of the platen. More preferably, polishing pad 210 includes 20 to 1,000 outwardly offset grooves in each polishing area 240, 242, 244, 246, 248, 250, 252, and 254. Optimally, polishing pad 210 includes 20 to 500 outwardly offset grooves in each polishing area 240, 242, 244, 246, 248, 250, 252, and 254.

Typically, the total number of outwardly offset grooves (such as 360, 362, 364, 166, 368, and 370) of polishing pad 210 is radial feed grooves 220, 222, 224, 226, 228, 230, 232, and 234 ( 8) At least 15 times the total. For example, the total number of outwardly biased grooves on polishing pad 210 is 20 to 1,000 times the total number of radial feed troughs 220, 222, 224, 226, 228, 230, 232, and 234 (8). Preferably, the total number of outwardly biased grooves on polishing pad 210 is 20 to 500 times the total number of radial feed troughs 220, 222, 224, 226, 228, 230, 232, and 234(8).

Referring to Figures 3 and 3A, the slurry flow vector illustrates how centrifugal motion of the polishing pad causes the polishing fluid to move outward through offset grooves 3-3 and 3a-3a. The arrows indicate the counterclockwise platen rotation direction, and DP represents the typical slurry drop point. The slurry vectors intersect at point W, which represents the point of slurry flow below the wafer. In the case of inwardly biased grooves (Fig. 3), V _ib represents the outward velocity of the slurry through the inwardly biased grooves 3-3, and _VN represents the direction perpendicular to the inwardly biased grooves 3-3 slurry flow rate. The resulting slurry flow rate _VT or total velocity is slowed relative to the wafer, thereby extending the residence time of the polishing solution under the wafer. In the case of the outwardly biased trenches (FIG. 3A), _Vob represents the outward velocity of the slurry through the outwardly biased trenches 3a-3a, and _VN denotes perpendicular to the inwardly biased trenches 3a-3a slurry flow rate. The resulting slurry flow rate _VT or total velocity becomes faster relative to the wafer, thereby reducing the residence time of the polishing solution under the wafer. With this groove configuration, the combination of platen speed and deflection angle controls the slurry residence time.

Referring to FIG. 4 , inwardly biased polishing pad 400 has three polishing regions 402 , 404 and 406 . Radial feed slots 408, 410, and 412 divide polishing pad 400 into equal-sized polishing regions 402, 404, and 406 that are 120 degrees apart. In an alternative embodiment not shown, the polishing area may be divided into two sizes, eg 100 degrees, 100 degrees and 160 degrees. In another alternative embodiment, the polishing area may be divided into three different sizes, eg, 100 degrees, 120 degrees, and 140 degrees. As polishing pad 400 rotates, the long offset trenches sweep across the wafer to increase removal rates. In the described embodiment, the radial feed grooves 408, 410 and 412 are preferably larger in cross section than the offset grooves to improve the distribution of the polishing liquid.

Referring to FIG. 4A , the outwardly biased polishing pad 450 has three polishing regions 452 , 454 and 456 . Radial feed slots 458, 460, and 462 divide polishing pad 450 into equal-sized polishing regions 452, 454, and 456 that are 120 degrees apart. In an alternative embodiment not shown, the polishing area may be divided into two sizes, eg 100 degrees, 100 degrees and 160 degrees. In another alternative embodiment, the polishing area may be divided into three different sizes, eg, 100 degrees, 120 degrees, and 140 degrees. As polishing pad 450 rotates, the long offset trenches sweep across the wafer to increase removal rates. In the described embodiment, the radial feed grooves 458, 460, and 462 are preferably larger in cross-section than the offset grooves to improve slurry distribution.

Referring to FIG. 5 , an inwardly biased polishing pad 500 has four polishing regions 502 , 504 , 506 and 508 . Radial feed slots 510, 512, 514, and 516 divide polishing pad 500 into equal-sized polishing regions 502, 504, 506, and 508 that are 90 degrees apart. In an alternative embodiment not shown, the polishing area may be divided into two sizes, eg, 80 degrees, 100 degrees, 80 degrees, and 100 degrees. In another alternative embodiment, the polishing area may be divided into four different sizes, eg, 70 degrees, 110 degrees, 80 degrees, and 100 degrees. In addition, the order of polishing areas can be changed. As polishing pad 500 rotates, the offset trenches sweep across the wafer to increase removal rates. In the described embodiment, the radial feed grooves 510, 512, 514 and 516 are preferably larger in cross section than the offset grooves to improve the distribution of the polishing liquid.

Referring to FIG. 5A , an outwardly biased polishing pad 550 has four polishing regions 552 , 554 , 556 and 558 . Radial feed slots 560, 562, 564, and 566 divide polishing pad 550 into equal-sized polishing regions 552, 554, 556, and 558 that are 90 degrees apart. In an alternative embodiment not shown, the polishing area may be divided into two sizes, eg, 80 degrees, 100 degrees, 80 degrees, and 100 degrees. In another alternative embodiment, the polishing area may be divided into four different sizes, eg, 70 degrees, 80 degrees, 100 degrees, and 110 degrees. In addition, the order of polishing areas can be changed. As polishing pad 550 rotates, the offset trenches sweep across the wafer to increase removal rates. In the described embodiment, the radial feed grooves 560, 562, 564, and 566 are preferably larger in cross-section than the offset grooves to improve slurry distribution.

Referring to FIG. 6 , inwardly biased polishing pad 600 has five polishing regions 602 , 604 , 606 , 608 and 610 . Radial feed slots 612, 614, 616, 618, and 620 divide polishing pad 600 into equal-sized polishing regions 602, 604, 606, 608, and 610 that are 72 degrees apart. In an alternative embodiment not shown, the polishing area may be divided into two sizes, eg, 60 degrees, 90 degrees, 60 degrees, 90 degrees, and 60 degrees. In another alternative embodiment, the polishing area may be divided into five different sizes, eg, 52 degrees, 62 degrees, 72 degrees, 82 degrees, and 92 degrees. In addition, the order of polishing areas can be changed. As the polishing pad 600 rotates, the offset grooves sweep across the wafer to increase removal rates, and additional radial feed troughs aid in slurry distribution. In the described embodiment, the radial feed grooves 612, 614, 616, 618, and 620 are preferably larger in cross-section than the offset grooves to improve the distribution of the slurry.

Referring to FIG. 6A , the outwardly biased polishing pad 650 has five polishing regions 652 , 654 , 656 , 658 and 660 . Radial feed slots 662, 664, 666, 668, and 670 divide polishing pad 650 into equal-sized polishing regions 652, 654, 656, 658, and 660 that are 72 degrees apart. In an alternative embodiment not shown, the polishing area may be divided into two sizes, eg, 60 degrees, 90 degrees, 60 degrees, 90 degrees, and 60 degrees. In another alternative embodiment, the polishing area may be divided into five different sizes, eg, 52 degrees, 62 degrees, 72 degrees, 82 degrees, and 92 degrees. In addition, the order of polishing areas can be changed. As the polishing pad 650 rotates, the offset grooves sweep across the wafer to increase removal rates, and additional radial feed troughs aid in slurry distribution. In the described embodiment, the radial feed grooves 662, 664, 666, 668 and 670 are preferably larger in cross section than the offset grooves to improve the distribution of the polishing liquid.

Referring to FIG. 7 , the inwardly biased polishing pad 700 has six polishing regions 702 , 704 , 706 , 708 , 710 and 712 . Radial feed slots 714, 716, 718, 720, 722, and 724 divide polishing pad 700 into equal-sized polishing regions 702, 704, 706, 708, 710, and 712 that are 60 degrees apart. In an alternative embodiment not shown, the polishing area may be divided into two sizes, eg, 50 degrees, 70 degrees, 50 degrees, 70 degrees, 50 degrees, and 70 degrees. In another alternative embodiment, the polishing area may be divided into six different sizes, eg, 30 degrees, 40 degrees, 50 degrees, 70 degrees, 80 degrees, and 90 degrees. In addition, the order of polishing areas can be changed. As the polishing pad 700 rotates, the offset grooves sweep across the wafer to increase removal rates, and additional radial feed troughs aid in slurry distribution. In the described embodiment, the radial feed grooves 714, 716, 718, 720, 722, and 724 are larger in cross-section than the offset grooves to improve slurry distribution.

Referring to FIG. 7A , an outwardly biased polishing pad 750 has six polishing regions 752 , 754 , 756 , 758 , 760 and 762 . Radial feed slots 764, 766, 768, 770, 772, and 774 divide polishing pad 750 into equal-sized polishing regions 752, 754, 756, 758, 760, and 762 that are 60 degrees apart. In an alternative embodiment not shown, the polishing area may be divided into two sizes, eg, 50 degrees, 70 degrees, 50 degrees, 70 degrees, 50 degrees, and 70 degrees. In another alternative embodiment, the polishing area may be divided into six different sizes, eg, 30 degrees, 40 degrees, 50 degrees, 70 degrees, 80 degrees, and 90 degrees. In addition, the order of polishing areas can be changed. As the polishing pad 750 rotates, the offset grooves sweep across the wafer to increase removal rates, and additional radial feed troughs aid in slurry distribution. In the described embodiment, the radial feed grooves 764, 766, 768, 770, 772 and 774 are preferably larger in cross section than the offset grooves to improve the distribution of the polishing liquid.

Referring to FIG. 1 , the inwardly biased polishing pad 10 has eight polishing regions 40 , 42 , 44 , 46 , 48 , 50 , 52 and 54 . Radial feed troughs 20, 22, 24, 26, 28, 30, 32, and 34 divide polishing pad 10 into equal-sized polishing regions 40, 42, 44, 46, 48, 50, 52, and 54 spaced 45 degrees apart. In an alternative embodiment not shown, the polishing area may be divided into two sizes, eg, 35 degrees, 55 degrees, 35 degrees, 55 degrees, 35 degrees, 55 degrees, 35 degrees, and 55 degrees. In another alternative embodiment, the polishing area may be divided into eight different sizes, such as 25 degrees, 30 degrees, 35 degrees, 40 degrees, 50 degrees, 55 degrees, 60 degrees, and 65 degrees. In addition, the order of polishing areas can be changed. As the polishing pad 10 rotates, the offset grooves sweep across the wafer to increase removal rates, and additional radial feed troughs aid in slurry distribution. In the described embodiment, the radial feed grooves 20, 22, 24, 26, 28, 30, 32 and 34 are preferably larger in cross section than the offset grooves to improve the distribution of the polishing liquid. Rotating the polishing pad alternately passes wafers over one radial feed slot and two radial feed slots.

Referring to FIG. 2 , the outwardly biased polishing pad 210 has eight polishing regions 240 , 242 , 244 , 246 , 248 , 250 , 252 and 254 . Radial feed slots 220, 222, 224, 226, 228, 230, 232, and 234 divide polishing pad 210 into polishing regions 240, 242, 244, 246, 248, 250, 252, and 254 that are 45 degrees apart. In an alternative embodiment not shown, the polishing area may be divided into two sizes, eg, 35 degrees, 55 degrees, 35 degrees, 55 degrees, 35 degrees, 55 degrees, 35 degrees, and 55 degrees. In another alternative embodiment, the polishing area may be divided into eight different sizes, such as 25 degrees, 30 degrees, 35 degrees, 40 degrees, 50 degrees, 55 degrees, 60 degrees, and 65 degrees. In addition, the order of polishing areas can be changed. As the polishing pad 210 rotates, the offset grooves sweep across the wafer to increase removal rates, and additional radial feed troughs aid in slurry distribution. In the described embodiment, the radial feed grooves 220, 222, 224, 226, 228, 230, 232, and 234 are larger in cross-section than the offset grooves to improve slurry distribution.

Referring to Figures 8 and 8A, bending the offset grooves 810 and 860 of the polishing pads 800 and 850, respectively, can promote uniform flow of the polishing liquid over the groove landing areas. Polishing pads 800 and 850 have outwardly offset trenches 810 and 860 . As the polishing pads 800 and 850 rotate, the polishing fluid flows out of the grooves 810 and 860 to the outer edges 812 and 862 . In grooves 810 and 860, the outward slope of the groove decreases as it travels outward, which slows the outward velocity and helps the slurry wet groove 810 during clockwise and counterclockwise rotation And the landing area near the end of 860.

For these configurations and for illustrative purposes, the deflection angle Θ is equal to the average angle of the curved offset trenches relative to the bisector represented by the dashed line. One way to measure the deflection angle as shown in Figure 8 is to draw an imaginary line 8-8 connecting adjacent radial feed troughs 820 and 830 along a single curved offset channel, and then measure the The angle (θ) or deflection angle at which the dotted bisector B ₈ intersects. Similarly, in Figure 8A, an imaginary line 8a-8a joins adjacent radial feed troughs 870 and 872 along a single curved offset groove, and then measures the angle that intersects the dashed bisector B _8a , which is equal to the deflection angle theta. It is important that at least a majority of each curved offset section has an inward or outward angle. Most of the offset trenches should preferably have the same offset. This is because having inwardly biased trench portions and outwardly biased trench portions tend to cancel each other out in terms of removal rate. Advantageously, all offset segments have an inward or outward offset.

9, polishing pad 900 has radial feed channels 910, 912, 914, and 916 that are curved. Feed troughs 910, 912, 914, and 916 are curved counterclockwise to improve fluid flow when polishing pad 900 is rotated clockwise. This shape accelerates the outward flow of the slurry to improve the distribution of slurry to the outer bias groove 920 during clockwise rotation, and slows the outward flow to reduce the slurry to the outer bias groove during counterclockwise rotation Distribution of slots 920. Alternatively, the radial feed trough can be bent in a clockwise direction (not shown) for the opposite effect. This shape slows the outward flow of the slurry to improve the distribution of the slurry to the outer bias grooves 920 during counterclockwise rotation, and accelerates the outward flow to reduce the slurry to the outer bias grooves during clockwise rotation Distribution of slots 920.

Measuring the deflection angle of FIG. ₉ with curved radial feed troughs 914 and 916 requires drawing the dashed radial lines Ra and Rb and an imaginary bisector B9 that bisects the dashed radial lines Ra and Rb. This illustrates the deflection angle θ of the outwardly biased trench ₉₃₀ that intersects the bisector B9. Chords Ra ₁ and Rb ₁ have equal lengths and are parallel radial lines Ra and Rb, respectively. Dashed line Ra ₁ -Rb ₁ connects the ends of chords Ra ₁ and Rb ₁ and intersects bisector B ₉ at offset trench 930 . The deflection angle of trench 930 is the angle or θ between bisector B ₉ and trench 930 . This embodiment has a constant θ along each offset groove throughout the polishing area.

10, polishing pad 1000 includes a combination of curved radial feed channels 1010, 1012, 1014, and 1016 and curved grooves 1020 that are biased outward. In particular, the groove pattern includes curved radial feed channels 1010 , 1012 , 1014 , and 1016 to fine-tune or adjust the polishing fluid near the outer edge 1022 of the polishing pad 1000 . In addition, the outwardly biased curved grooves 1020 serve to balance the flow of polishing fluid onto the landing areas within the polishing regions 1030 , 1032 and 1034 .

Measuring the deflection angle of Figure 10 with curved radial feed troughs 1014 and ₁₀₁₆ requires drawing the radial dashed lines Ra and Rb and an imaginary bisector B10 that bisects the radial dashed lines Ra and Rb. This illustrates the deflection angle θ of the outwardly offset trench 1040 that intersects the bisector B ₁₀ . Chords Ra ₁ and Rb ₁ have equal lengths and are parallel radial lines Ra and Rb, respectively. Dashed line Ra ₁ -Rb ₁ connects the ends of chords Ra ₁ and Rb ₁ and intersects bisector B ₉ at offset trench 104 . The deflection angle of the groove 1040 is the angle or θ between the bisector B ₁₀ and the line connecting the ends of the groove 1040 . θ for this embodiment increases as the spacing of each offset trench from the polishing pad 1000 increases.

11, 11A, and 11B, polishing pad 1100 includes stepped radial feed channels 1110, 1112, 1114, and 1116. This shape slows the outward flow of the slurry to improve the distribution of the slurry to the outer bias grooves 1120, 1122 and 1124 during clockwise rotation, and accelerates the outward flow to reduce the slurry to the outside during counterclockwise rotation Distribution of external bias trenches 1120, 1122, and 1124. Alternatively, the radial feed trough can be bent in a clockwise direction (not shown) for the opposite effect. This shape slows the outward flow of the slurry to improve the distribution of the slurry to the outer bias grooves 1120, 1122 and 1124 during counterclockwise rotation, and slows the outward flow to reduce the slurry during clockwise rotation The distribution of trenches 1120, 1122, and 1124 is biased outward. The outwardly curved radially offset grooves 1120, the inwardly radially offset grooves 1122, and the inwardly parallel radially offset grooves 1124 are all used to adjust the residence time of the polishing solution under the wafer and to fine-tune the polishing profile. In addition, the edge profile can be adjusted by adjusting the platen or wafer rotation speed. For example, increasing the platen or wafer speed can quickly polish the center to a flat profile. This effect becomes much more pronounced when the wafer does not oscillate between the center and edge of the polishing pad.

Referring to Figure 11, phantom lines 11-11 connect a single offset trench. The angle between the imaginary line 11-11 and the bisector B _11-1 of the radial feed troughs 1114 and 1116 represents θ ₁ or the deflection angle of the first portion of the polishing area. This portion of the polishing area has an offset angle that decreases with the spacing of each offset groove from the center of the polishing pad.

The second area requires the drawing of radial lines Ra and Rb and B _11-2 that bisects radial lines Ra and Rb. The radial chords Ra ₁ and Rb ₁ have equal lengths and are parallel radial lines Ra and Rb, respectively. The dashed line B _11-2 represents the bisectors of these radial chords. An imaginary line Ra ₁ -Rb ₁ connects Ra ₁ and Rb ₁ and passes through the intersection of offset trench 1130 and bisector B _11-2 . The intersection of the line connecting the ends of the offset trench 1130 and the bisector B _11-2 represents the deflection angle or θ ₂ . This portion of the polishing area also has an offset angle that decreases with the spacing of each offset groove from the center of the polishing pad.

12 and 12A, polishing pad 1200 may contain a series of stepped offset grooves 1202 and 1204 connecting radial feed troughs 1210, 1220, 1230 and 1240, respectively. Stepped offset trenches 1202 and 1204 have sections 1202a and 1202b, and 1204 has sections 1204a and 1204b, each separated by a dashed line for illustration purposes. Figure 12 has an inwardly offset stepped trench 1202 that is divided into equal parts: trench segments 1202a and 1202b. In this configuration, the slurry first passes through the shallower offset trench section 1202a, followed by the trench section 1202b with a steeper slope at an increasing rate. Figure 12A has a stepped offset trench 1204 that is divided into unequal parts: trench segments 1204a and 1204b. In this configuration, the slurry first passes through the steeper offset trench section 1204a, followed by the trench section 1204b with a shallower slope at a reduced rate. Wafer profile and edge profile can be adjusted using segment pitch and slope.

13, polishing pad 1300 includes outwardly biased stepped grooves 1302 interconnecting adjacent stepped radial feed grooves 1310, 1320, 1330, and 1340. The stepped offset trench 1302 has sections 1302a and 1202b, each separated by a dashed line for illustration purposes. Both the step position and step slope of the radial feed trough and the stepped offset groove affect the polishing removal rate, wafer profile and edge profile.

Referring to Figures 14, 14A, 14B, and 14C, the polishing pad may include two or more groove regions having different pitches or different cross-sectional areas. Figures 14, 14A, 14C each include inwardly spaced regions with three regions: (a) trenches with a first normal pitch, (b) trenches with increased pitch and (c) pitch equal to region (a) groove. This trench spacing effectively eliminates the center fast wafer profile. By adjusting the width of each trench region and the trench density within each trench region, the wafer profile can be fine-tuned. Adjusting the trench spacing has a particular effect on improving the wafer edge profile. As shown in FIG. 14, the offset grooves may be parallel linear grooves, parallel curved grooves or stepped grooves. The grooves may have equal or unequal spacing.

Referring to Figures 15, 15A, 15B, and 15C, the polishing pad may include two or more groove regions with different pitches or different cross-sectional areas. Figures 15, 15A, 15B and 15C all include inwardly spaced regions with three regions: (A) trenches with a first increased pitch, (B) trenches with normal pitch and (C) equal pitch regions (A) The groove. This trench spacing effectively eliminates the center slow wafer profile. By adjusting the width of each trench region and the trench density within each trench region, the wafer profile can be fine-tuned. Adjusting the trench spacing has a particular effect on improving the wafer edge profile. As shown in FIG. 15, the offset grooves may be parallel linear grooves, parallel curved grooves or stepped grooves. The grooves may have equal or unequal spacing.

10‧‧‧Polishing pad of the present invention 12‧‧‧Polishing layer 16‧‧‧Center 18‧‧‧Outer edge 19‧‧‧Peripheral arc 20‧‧‧Radial feed groove 20a‧‧‧Radial feed Trough section 20b‧‧‧Radial feed trough section 20c‧‧‧Radial feed trough section 20d‧‧‧Radial feed trough section 20e‧‧‧Radial feed trough section 22‧‧ ‧Radial feed trough 22a‧‧‧Radial feed trough section 22b‧‧‧Radial feed trough section 22c‧‧‧Radial feed trough section 22d‧‧‧Radial feed trough section 22e‧‧‧Radial feed chute 24‧‧‧Radial feed chute26‧‧‧Radial feed chute28‧‧‧Radial feed chute30‧‧‧Radial feed chute32‧‧ ‧Radial feed slot 34‧‧‧Radial feed slot 36‧‧‧Circular groove 40‧‧‧Polishing area 42‧‧‧Polishing area 44‧‧‧Polishing area 46‧‧‧Polishing area 48‧‧ ‧Polishing area 50‧‧‧Polishing area 52‧‧‧Polishing area 54‧‧‧Polishing area 60‧‧‧Trapezoidal groove area 60a‧‧‧Landing area 61a‧‧‧Landing area 62‧‧‧Trapezoidal groove area 62a ‧‧‧Landing area 63a‧‧‧Landing area 64‧‧‧Trapezoidal groove area 66‧‧‧Trapezoidal groove area 68‧‧‧Trapezoidal groove area 70 ‧‧‧Trapezoidal trench area 84‧‧‧Trapezoidal trench area 86‧‧‧Trapezoidal trench area 88‧‧‧Trapezoidal trench area 90‧‧‧Trapezoidal trench area 92‧‧‧Trapezoidal trench area 94‧‧ ‧Trapezoidal groove area 96‧‧‧Trapezoidal groove area 98‧‧‧Trapezoidal groove area 160‧‧‧Offset groove 160a‧‧‧Outer wall 160b‧‧‧Inner wall 161‧‧‧Offset groove 161a‧ ‧‧Outer wall 161b‧‧‧Inner wall 162‧‧‧Offset groove 162a‧‧‧Outer wall 163‧‧‧Offset groove 163a‧‧‧Outer wall 164‧‧‧Substrate groove 166‧‧‧Substrate groove 168 ‧‧‧Substrate groove 170‧‧‧Substrate groove 210‧‧‧Polishing pad 212 of the present invention‧‧‧Polishing layer 214‧‧‧Thickness 216 Arc 220‧‧‧Radial feed chute 220a‧‧‧Radial feed chute section/Side section 220b‧‧‧Radial feed chute section/Side section 220c‧‧‧Radial feed chute section/ Side section 220d‧‧‧Radial feed chute section/Side section 220e‧‧‧Radial feed chute section/Side section 222‧‧‧Radial feed chute 222a‧‧‧Radial feed chute section /Side segment 222b‧‧‧Radial feed chute segment/Side segment 222c‧‧‧Radial feed chute segment/Side segment 222d‧‧‧Radial feed chute segment/Side segment 222e‧‧‧diameter Toward feed chute section/side section 224‧‧‧Radial feed chute 226‧‧‧Radial feed chute 228‧‧‧Radial feed chute 230‧‧‧Radial feed chute 232‧‧‧dia Toward feed chute 234‧‧‧Radial feed chute 23 6‧‧‧Circular grooves 240‧‧‧Polishing area 242‧‧‧Polishing area 244‧‧‧Polishing area 246‧‧‧Polishing area 248‧‧‧Polishing area 250‧‧‧Polishing area252‧‧‧Polishing area 254‧‧‧Polishing area 260‧‧‧Trapezoidal groove area 260a‧‧‧Landing area 261a‧‧‧Landing area 262‧‧‧Trapezoidal groove area 262a‧‧‧Landing area 263a‧‧‧Landing area 264‧‧‧ Trapezoidal trench area 266‧‧‧Trapezoidal trench area 268‧‧‧Trapezoidal trench area 270‧‧‧Trapezoidal trench area 280‧‧‧Trapezoidal trench area 282‧‧‧Trapezoidal trench area 284‧‧‧Trapezoidal trench area 286‧‧‧Trapezoidal trench area288‧‧‧Trapezoidal trench area290‧‧‧Trapezoidal trench area292‧‧‧Trapezoidal trench area294‧‧‧Trapezoidal trench area296‧‧‧Trapezoidal trench area360‧ ‧‧Offset groove/base segment 360a‧‧‧Outer wall 360b‧‧‧Inner wall 361‧‧‧Offset groove 361a‧‧‧Outer wall 361b‧‧‧Inner wall 362‧‧‧Offset groove/base segment 362a‧‧‧Outer wall 370‧‧‧Base section 400‧‧‧Inward offset polishing pad 402‧‧‧Polishing area 404‧‧‧Polishing area 406‧‧‧Polishing area 408‧‧‧Radial feed slot 410‧ ‧‧Radial feed slot 412‧‧‧Radial feed slot 450‧‧‧Outwardly offset polishing pad 452‧‧‧Polishing area 454‧‧‧Polishing area 456‧‧‧Polishing area 458‧‧‧Radial Feed chute 460‧‧‧Radial feed chute 462‧‧‧Radial feed chute 500‧‧‧Inward offset polishing pad 502‧‧‧Polishing area 504‧‧‧Polishing area 506‧‧‧Polishing area 508 ‧‧‧Polishing area 510‧‧‧Radial feed slot 512‧‧‧Radial feed slot 514‧‧‧Radial feed slot 516‧‧‧Radial feed slot 550‧‧‧Outward offset polishing Pad 552‧‧‧Polishing area 554‧‧‧Polishing area 556‧‧‧Polishing area 558‧‧‧Polishing area 560‧‧‧Radial feed slot 562‧‧‧Radial feed slot 564‧‧‧Radial feed slot Feed slot 566‧‧‧Radial feed slot 600‧‧‧Inward offset polishing pad 602‧‧‧Polishing area 604‧‧‧Polishing area 606‧‧‧Polishing area 608‧‧‧Polishing area 610‧‧‧Polishing Area 612‧‧‧Radial feed slot 614‧‧‧Radial feed slot 616‧‧‧Radial feed slot 618‧‧‧Radial feed slot 620‧‧‧Radial feed slot 650‧‧‧ Outwardly offset polishing pad 652‧‧‧Polishing area 654‧‧‧Polishing area 656‧‧‧Polishing area 658‧‧‧Polishing area 660‧‧‧Polishing area 662‧‧‧Radial feed slot 664‧‧‧dia Toward feed chute 666‧‧‧Radial feed chute 668‧‧‧Radial feed chute 670‧‧‧Radial feed chute 700‧‧‧Inward offset polishing pad 702‧‧‧ Polished area 704‧‧‧Polished area 706‧‧‧Polished area 708‧‧‧Polished area 710‧‧‧Polished area 712‧‧‧Polished area 714‧‧‧Radial feed slot 716‧‧‧Radial feed slot 718‧‧‧Radial feed slot 720‧‧‧Radial feed slot 722‧‧‧Radial feed slot 724‧‧‧Radial feed slot 750‧‧‧Outwardly offset polishing pad 752‧‧‧ Polished area 754‧‧‧Polished area 756‧‧‧Polished area 758‧‧‧Polished area 760‧‧‧Polished area 762‧‧‧Polished area 764‧‧‧Radial feed slot 766‧‧‧Radial feed slot 768‧‧‧Radial feed slot 770‧‧‧Radial feed slot 772‧‧‧Radial feed slot 774‧‧‧Radial feed slot 800‧‧‧Polishing pad 810‧‧‧Offset slot 820‧‧‧Radial feed slot 830‧‧‧Radial feed slot 850‧‧‧Polishing pad 860‧‧‧Offset slot 862‧‧‧Outer edge 870‧‧‧Radial feed slot 872‧‧ ‧Radial feed slot 900‧‧‧Polishing pad 910‧‧‧Radial feed slot 912‧‧‧Radial feed slot 914‧‧‧Radial feed slot 916‧‧‧Radial feed slot 920‧ ‧‧External offset groove 930‧‧‧Offset groove 1000‧‧‧Polishing pad 1010‧‧‧Radial feed groove 1012‧‧‧Radial feed groove 1014‧‧‧Radial feed groove 1016‧ ‧‧Radial feed slot 1020‧‧‧Outwardly offset curved groove 1022‧‧‧Outer edge 1030‧‧‧Polishing area 1032‧‧‧Polishing area 1034‧‧‧Polishing area 1040‧‧‧Outwardly offsetting Groove 1100‧‧‧Polishing Pad 1110‧‧‧Trapezoidal Radial Feed Slot 1112‧‧‧Trapezoidal Radial Feed Slot 1114‧‧‧Trapezoidal Radial Feed Slot 1116‧‧‧Trapezoidal Radial Feed Slot Feed trough 1120‧‧‧External offset groove 1122‧‧‧External offset groove 1124‧‧‧External offset groove 1130‧‧‧Offset groove 1200‧‧‧Polishing pad 1202‧‧‧Trapezoidal offset Set groove 1202a‧‧‧Section 1202b‧‧‧Section 1204‧‧‧Trapezoidal offset groove 1204a‧‧‧Section 1204b‧‧‧Section 1210‧‧‧Radial feed slot 1220‧‧‧ Radial Feed Slot 1230‧‧‧Radial Feed Slot 1240‧‧‧Radial Feed Slot 1300‧‧‧Polishing Pad 1302‧‧‧Outwardly Biased Trapezoidal Groove 1302a‧‧‧Section 1310‧‧ ‧Trapezoidal radial feed slot 1320‧‧‧Trapezoidal radial feed slot 1330‧‧‧Trapezoidal radial feed slot 1340‧‧‧Trapezoidal radial feed slot r ₁ ‧‧‧Radius r ₂ ‧ ‧‧Radius α ₁ ‧‧‧Angle β ₁ ‧‧‧Angle α ₂ ‧‧‧Angle β ₂ ‧‧‧Angle θ‧‧‧Deflection angle θ ₁ ‧‧‧Deflection angle θ ₂ ‧‧‧Deflection angle AA‧‧ ‧Dotted line V _T ‧‧‧Slurry flow rate V _N ‧‧‧Slurry flow rate V _ib ‧‧‧to External speed V _ob ‧‧‧Outward speed w‧‧‧Point DP‧‧‧Drop point of slurry 8-8‧‧‧Imaginary line 8a-8a‧‧‧Imaginary line B ₈ ‧‧‧bisector B _8a ‧‧ ‧bisector B ₉ ‧‧‧bisector B _{10 ‧‧‧bisector} B _11-1 ‧‧‧bisector B _11-2 ‧‧Radial dashed line Rb ₁ ‧‧‧chord Ra ₁ -Rb ₁ ‧‧‧dashed line

1 is a schematic top view of an inwardly biased polishing pad having eight polishing zones, each having a series of inwardly biased grooves connecting adjacent radial feed troughs. FIG. 1A is a partially cut-away schematic top view of the inwardly biased polishing pad of FIG. 1 . FIG. 1B is a partially cut-away schematic top view of one of the series of non-isosceles trapezoidal grooves of FIG. 1A rotated so that the sides of the trapezoid are parallel to the bottom of the figure. 1C is a partial cutaway schematic view of the radial feed slot and interconnected inwardly biased slot of FIG. 1 . 2 is a schematic top view of an outwardly biased polishing pad having eight polishing zones, each having a series of outwardly biased grooves connecting adjacent radial feed troughs. FIG. 2A is a partially cut-away schematic top view of the outwardly biased polishing pad of FIG. 2 . Figure 2B is a partially cut-away schematic top view of one of the series of non-isosceles trapezoidal grooves of Figure 2A, rotated so that the trapezoid sides are parallel to the bottom of the figure. FIG. 2C is a partial cut-away schematic view of the radial feed trough of FIG. 2 and the interconnected outwardly biased grooves. Figure 3 schematically depicts how the inwardly biased grooves direct the slurry towards the outer edge of the polishing pad to prolong the residence time of the slurry under the wafer with counterclockwise rotation of the platen. Figure 3A schematically depicts how the outwardly biased grooves direct the slurry towards the outer edge of the polishing pad to reduce the residence time of the slurry under the wafer with counterclockwise rotation of the platen. 4 is a schematic top view of an inwardly biased polishing pad having three polishing regions, each having a series of inwardly biased grooves connecting adjacent radial feed troughs. 4A is a schematic top view of an outwardly biased polishing pad having three polishing regions, each having a series of outwardly biased grooves connecting adjacent radial feed troughs. 5 is a schematic top view of an inwardly biased polishing pad having four polishing regions, each having a series of inwardly biased grooves connecting adjacent radial feed troughs. 5A is a schematic top view of an outwardly biased polishing pad having four polishing regions, each having a series of outwardly biased grooves connecting adjacent radial feed troughs. 6 is a schematic top view of an inwardly biased polishing pad having five polishing regions, each having a series of inwardly biased grooves connecting adjacent radial feed troughs. 6A is a schematic top view of an outwardly biased polishing pad having five polishing zones, each having a series of outwardly biased grooves connecting adjacent radial feed troughs. 7 is a schematic top view of an inwardly biased polishing pad having six polishing regions, each having a series of inwardly biased grooves connecting adjacent radial feed troughs. 7A is a schematic top view of an outwardly biased polishing pad having six polishing regions, each having a series of outwardly biased grooves connecting adjacent radial feed troughs. Figure 8 is a half-cut schematic top view of an outwardly offset polishing pad having eight polishing zones, each having a series of outwardly offset curved grooves connecting adjacent radial feed troughs. 8A is a half-cut schematic top view of an inwardly biased polishing pad having eight polishing regions each having a series of inwardly biased curved grooves connecting adjacent radial feed troughs. Figure 9 is a half-cut schematic top view of an outwardly biased polishing pad having eight polishing zones each having a series of outwardly biased grooves connecting adjacent curved radial feed troughs. 10 is a half-cut schematic top view of an outwardly offset polishing pad having eight polishing zones, each having a series of outwardly offset curved grooves connecting adjacent curved radial feed troughs. Figure 11 is a half-cut schematic top view of an outwardly offset polishing pad having eight polishing zones each having a series of outwardly offset curved grooves connecting adjacent stepped radial feed troughs. 11A is a half-cut schematic top view of an inwardly biased polishing pad having eight polishing regions each having a series of inwardly biased curved grooves connecting adjacent stepped radial feed troughs. 11B is a half-cut schematic top view of an inwardly biased polishing pad having eight polishing regions, each having a series of inwardly biased curved grooves connecting adjacent stepped radial feed troughs. Figure 12 is a half-cut schematic top view of an inwardly offset polishing pad having eight polishing zones, each having a series of inwardly offset stepped grooves connecting adjacent radial feed troughs. Figure 12A is a half-cut schematic top view of an outwardly offset polishing pad having eight polishing zones, each having a series of outwardly offset stepped grooves connecting adjacent radial feed troughs. 13 is a half-cut schematic top view of an outwardly offset polishing pad having eight polishing zones each having a series of outwardly offset stepped grooves connecting adjacent stepped radial feed grooves . 14 is a half-cut schematic top view of an inwardly biased polishing pad having eight polishing regions each having a series of inwardly biased stepped grooves of increasing spacing located in Between two series of inwardly offset stepped grooves of standard spacing, all grooves connecting adjacent radial feed troughs. 14A is a half-cut schematic top view of an outwardly offset polishing pad having eight polishing regions each having a series of outwardly offset curved grooves of increasing spacing, the curved grooves being at standard spacing Between two series of outwardly offset curved grooves, all grooves connect adjacent radial feed troughs. 14B is a half-cut schematic top view of an inwardly offset polishing pad having eight polishing regions each having a series of inwardly biased curved grooves of increasing spacing, the curved grooves being at standard spacing Between two series of inwardly offset curved grooves, all grooves connecting adjacent radial feed troughs. 14C is a schematic top half view of an inwardly offset polishing pad having eight polishing regions each having a series of inwardly biased grooves of increasing spacing, the curved grooves being located at standard spacing Between two series of inwardly offset grooves, all grooves connect adjacent radial feed troughs. 15 is a schematic top half view of an inwardly biased polishing pad having eight polishing regions each having a series of inwardly biased stepped grooves of standard spacing, the stepped grooves being located in Between two series of inwardly offset stepped grooves of increasing spacing, all of which connect adjacent radial feed troughs. 15A is a half-cut schematic top view of an outwardly biased polishing pad having eight polishing regions each having a series of outwardly biased curved grooves of standard spacing, the curved grooves being located at increasing spacing Between two series of outwardly offset curved grooves, all grooves connect adjacent radial feed troughs. 15B is a half-cut schematic top view of an inwardly biased polishing pad having eight polishing regions each having a series of inwardly biased curved grooves of standard spacing, the curved grooves being located at increasing spacing Between two series of inwardly offset curved grooves, all grooves connecting adjacent radial feed troughs. 15C is a schematic top half view of an inwardly biased polishing pad having eight polishing regions each having a series of inwardly biased grooves of standard spacing, the inwardly biased grooves located at Between two series of inwardly offset grooves of increasing spacing, all of which connect adjacent radial feed troughs.

10‧‧‧Polishing pad of the present invention

12‧‧‧Polishing layer

16‧‧‧Centre

18‧‧‧Outer edge

19‧‧‧Circular arc

20‧‧‧Radial feed chute

22‧‧‧Radial feed chute

24‧‧‧Radial feed chute

26‧‧‧Radial feed chute

28‧‧‧Radial feed chute

30‧‧‧Radial feed chute

32‧‧‧Radial feed chute

34‧‧‧Radial feed chute

36‧‧‧Circular groove

40‧‧‧Polished area

42‧‧‧Polished area

44‧‧‧Polished area

46‧‧‧Polished area

48‧‧‧Polished area

50‧‧‧Polished area

52‧‧‧Polished area

54‧‧‧Polished area

Claims (8)

A method for polishing or planarizing a wafer of at least one of semiconductor, optical, and magnetic substrates, the method comprising: a spinning polishing pad having: a polishing layer having a polymer matrix and a thickness , the polishing layer includes a center, an outer edge and a radius extending from the center of the polishing pad to the outer edge; a radial feed slot located in the polishing layer, the radial feed slot will The polishing layer is divided into polishing areas, which are circular sectors bounded by two adjacent radial feed grooves, and most of the offset grooves sweep across the wafer in the same direction under the wafer, so said radial feed troughs extending from a location adjacent said center to at least a location adjacent said outer edge; and each polishing zone comprising a series of offset grooves connecting a pair of adjacent radial feed troughs , the majority of the offset grooves are biased inward toward the center of the polishing pad or outwardly toward the outer edge of the polishing pad, the inward and outward bias grooves allow polishing Fluid moves toward the outer edge of the polishing pad and toward or away from the wafer depending on the inward or outward bias and the direction of rotation of the polishing pad; dispensing the polishing fluid to on the rotating polishing pad and into the radial feed slot and the series of offset grooves; and rotating the wafer against the rotating polishing pad with multiple rotations of the polishing pad , to adjust polishing by the following options: i) During counterclockwise rotation of the polishing pad, if the series of offset grooves are inwardly biased towards the center of the rotating polishing pad, the circular sector The outward flow of the slurry in the series of offset grooves in the series extends the residence time of the slurry under the wafer; or ii) during clockwise rotation of the polishing pad, if the series Offset grooves are deflected outward toward the outer edge of the rotating polishing pad, extending the flow of the slurry in the circular sector by the outward flow of the slurry in the series of offset grooves The residence time under the wafer, and wherein the misalignment of the offset grooves between adjacent polishing regions promotes the flow of the polishing liquid down the radial feed trough to improve slurry distribution. The method of claim 1, wherein the wafer is positioned along the radius, approaching the outer edge of the polishing pad from the center of the polishing pad, and then approaching the polishing the center of the pad to increase the removal rate of at least one component in the wafer. The method of claim 1, wherein rotating the polishing pad causes used polishing fluid to pass through a portion of the series of offset grooves to the outer edge of the polishing pad to allow fresh polishing fluid flow under the wafer. The method of claim 1 , wherein the series of offset trenches appear as parallel trenches extending the residence time of the polishing solution under the wafer. A method for polishing or planarizing a wafer of at least one of semiconductor, optical, and magnetic substrates, the method comprising: a spinning polishing pad having: a polishing layer having a polymer matrix and a thickness , the polishing layer includes a center, an outer edge and a radius extending from the center of the polishing pad to the outer edge; a radial feed slot located in the polishing layer, the radial feed slot will The polishing layer is divided into polishing areas, which are circular sectors bounded by two adjacent radial feed grooves, a bisector that bisects the polishing area, with most of the offset grooves under the wafer sweeping the wafer in the same direction, the radial feed slot extending from a location adjacent to the center at least to a location adjacent to the outer edge; and each polishing area comprising connecting a pair of adjacent radial a series of offset grooves of the feed chute, the majority of the offset grooves being offset inwardly towards the center of the polishing pad at an angle of 20° to 85° from the bisector or at an angle from the bisector The bisector is biased outwardly toward the outer edge of the polishing pad at an angle of 95° to 160°, and the inward and outward biasing grooves move the polishing fluid toward and away from the outer edge of the polishing pad. toward the wafer or away from the wafer depending on the inward or outward bias and the direction of rotation of the polishing pad; dispensing slurry onto the rotating polishing pad and into the radial feed chute and the series of offset grooves; and in the case of multiple rotations of the polishing pad, causing the wafer to be rotated against the rotating polishing pad rotation to adjust polishing by the following options: i) During counterclockwise rotation of the polishing pad, if the series of offset grooves are inwardly biased towards the center of the rotating polishing pad, the circular sector The outward flow of the slurry in the series of offset grooves in the zone prolongs the residence time of the slurry under the wafer; or ii) during clockwise rotation of the polishing pad, if the A series of offset grooves are deflected outwardly towards the outer edge of the rotating polishing pad, then the polishing liquid is extended in the circular sector by the outward flow of the polishing liquid in the series of offset grooves in the circular sector. The residence time under the wafer, and wherein the misalignment of the offset grooves between adjacent polishing regions, promotes the flow of the polishing liquid down the radial feeder grooves to improve slurry distribution. The method of claim 5, wherein the wafer is positioned along the radius, approaching the outer edge of the polishing pad from the center of the polishing pad, and then approaching the polishing the center of the pad to increase the removal rate of at least one component in the wafer. 5. The method of claim 5, wherein rotating the polishing pad causes used polishing fluid to pass through a portion of the series of offset grooves to the outer edge of the polishing pad to allow fresh polishing fluid to settle in flow under the wafer. The method of claim 5, wherein the series of offset trenches appear as parallel trenches extending the residence time of the polishing solution under the wafer.

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